The speed of computers has been continuously increasing in recent years. Physical size limitations of the components, however, are imposing limitations on future speed increases. That is, the dimensions of the conductors formed in the integrated circuits have shrunk to the point the conductors are themselves beginning to restrict current flow.
One approach to increasing the speed of computers has been to use light to transmit data between components of a computer. The use of fiber optic transmission lines has several advantages over conventional electrical cables. For example, fiber optic materials frequently cost less than electrical cables. Moreover, the power required to drive optic signals is frequently less than that required for many electrical cables. Furthermore, optical transmission of data provides an enhanced rate of information transfer over longer distances. Using optical transmission, manufacturers can mount a light source on one component, such as a microprocessor, and a receiver on another component, such as a memory device, and connect the light source and the receiver with an optic fiber.
In practice, manufacturers use transceivers that convert electrical signals to transmitted optical signals and convert received optical signals to electrical signals. These transceivers, known as opto-electronic devices, must be precisely aligned with optical fibers to transmit the data between various components. A major disadvantage of the use of opto-electronic devices is the difficulty of aligning the output of the opto-electronic device with the optic fiber. In particular, current alignment procedures are very labor intensive using very expensive machines. Hence, their cost makes them relatively expensive and generally limits their applicability. If the alignment could be automated, a substantial savings in manufacturing time and money could be achieved, allowing wider application of the technology.